Restricting Transactions

The following restrictions on transactions
are enforced by the container and must be observed as session beans
are developed:

A session bean can participate in, at most, a single
transaction at a time.

If a session bean is participating in a transaction,
a client cannot invoke a method on the bean such that the trans-attribute element (or @TransactionAttribute annotation)
in the ejb-jar.xml file would cause the container
to execute the method in a different or unspecified transaction context
or an exception is thrown.

If a session bean instance is participating in a transaction,
a client cannot invoke the remove method on the
session object’s home or business interface object, or an exception
is thrown.